When I click invest a screen appears asking for some details and I have some questions, why you ask for the amount of dollar? The price of crypto is all over the place, why don’t you ask about the amount of BTC or ETH that is going to be invested instead? And why do you need a phone number at all?
whether they use the unit btc or usd because there'll be real time converter. basically the unit usd is more easy to use and understand as the price of cryptocurrencies are totally
changing so a stable currency is needed, if you read the whitepaper there are some conversions there like $1 = 1 token so it'll be unfair if they'd use the unit btc on this whether
the price falls or rise. e.g. A wants to buy 2 token which is 50K sats/piece so regardless if the price goes up or down the amount of the token you'll received is be fixed but if its
proportional to usd you can get more if the price rises.
as for the phone number, maybe they'll use it to verify that its you send a code or something or mmaybe send notifications. you can trust this team. yahoo vouched for them